Assessment of pavement performance is essential in determining the serviceability and structural state of the pavement structure. Pavement failure and deterioration always commence immediately after the road has been opened to traffic. Several factors contributing to pavement failure and damage include traffic load, soil, environmental, economic, and stress distribution factor. Therefore, flexible pavement failure and deterioration are well-defined by alligator cracks, concentrated potholes, ruts, settlement, and localised depression. Pavement evaluation determines highway sections' functional and structural conditions for frequent monitoring or planning for maintenance. Kampi ya Moto-Eldama Ravine- Kamwasor (B77) road is a Kenya National Highways, Authority (KeNHA) class B road constructed in 2008. The length of the road is approximately 79.5 Km. However, the pavement had numerous distress features which developed even before the design life of the pavement was attained. The study, therefore, concentrated on evaluating the performance of the pavement to identify the type and level of severity of pavement distress; to establish a surface condition by measuring the level of roughness and rut depth and to perform a visual evaluation survey of the existing flexible pavement distresses; to identify the reason of structural and functional failures on Eldama Ravine-Kamwosor, and finally, to establish the residual structural strength of the existing flexible pavement and suggests the most viable maintenance intervention measures.